The source of a 2006 outbreak of fungal eye infections among contact lens wearers is a fungus known as Fusarium, found in places such as soil, water, and organic matter including plants. Ordinarily, it is rare for this fungus to invade and damage the eye. But symptoms can be severe, and if untreated, the infection may become so eye-damaging that a corneal transplant is required. For more information, please see our fungal keratitis eye infection article.